What is HDL cholesterol?
CBS News Medical Correspondent Dr. Jennifer Ashton said, "So many people hear the word cholesterol and they think it's got to be bad. The fact of the matter is like most things in medicine, we need it in moderation. It's very important to the function of our cells. When you talk about the difference between good and bad cholesterol, good way to remember, H-cholesterol, HDL is the healthy or good cholesterol. LDL is the lousy or bad."
Ashton added, "There are two numbers you need to know. You want your LDL or bad cholesterol below 100. And your HDL or good cholesterol over 60."
As for the study, Ashton said the findings are based on research conducted on 1,130 people, age 65 and over.
"(They) divided them into groups based on their HDL or healthy cholesterol number and found that those with an HDL above 65 were at a 60 percent lower risk of having Alzheimer's disease. This is what we call an associated finding. They didn't explain cause and effect, but we know very clearly that what's good for the heart is also good for the brain and vice versa, so that's one theory."
So how can you boost your good cholesterol?
Ashton suggests behavioral changes.
She said, "We have to remember 75 percent of your cholesterol comes from our body, 25 percent of it comes from our food intake. So when you talk about elevating the HDL or the good cholesterol, if you smoke, stop. That can increase your HDL numbers by 10 percent. Exercise can boost your HDL. Very important. And eating a diet low in cash high carbohydrates also can raise that money."
"Early Show" co-anchor Betty Nguyen said, "I imagine diet is something a lot of people will be trying to fix or moderate."
Ashton said, "Absolutely."
To help lower your bad cholesterol, Ashton suggests substituting vegetable oils or nuts for saturated fats.
"So if you're cooking with butter now," she said, "switch over to a vegetable oil whenever possible -- or olive oil."
For breakfast, Ashton said oatmeal can be a great in lowering your LDL numbers.
She added, "And if you like your eggs, you don't have to give them up, but just substitute egg whites for a whole egg, and you will dramatically reduce your LDL cholesterol intake."
"Now, some people might still need medication," she said, "but these are important things they can do."